有时候我们需要传输密码，并且每次传输的内容不一样，我们可以使用AES对称加密。一个密钥为对称令牌，再加一个随机数为向量值，这样子每次生成的密文都不一样了。

添加依赖

dependencies:
  encrypt: ^5.0.1

Pub get

下载依赖

封装工具类

aes_cipher.dart

import 'package:encrypt/encrypt.dart';
import 'dart:convert';

class AESCipher {
  final Encrypter _encrypter;
  final IV _iv;

  AESCipher(String keyStr, String ivStr)
      : assert(keyStr.length == 16 || keyStr.length == 24 || keyStr.length == 32,
  'Key must be 16, 24, or 32 characters'),
        assert(ivStr.length == 16, 'IV must be 16 characters'),
        _encrypter = Encrypter(AES(
          Key.fromUtf8(keyStr),
          mode: AESMode.cbc,
          padding: 'PKCS7',
        )),
        _iv = IV.fromUtf8(ivStr);

  /// 加密返回 Base64 编码字符串
  String encrypt(String plainText) {
    final encrypted = _encrypter.encrypt(plainText, iv: _iv);
    return encrypted.base64;
  }

  /// 解密 Base64 编码字符串
  String decrypt(String base64CipherText) {
    final encrypted = Encrypted.fromBase64(base64CipherText);
    return _encrypter.decrypt(encrypted, iv: _iv);
  }
}

调用示例

    String secretKey = "xxxxx";
    String nonce = TextUtils.randomString();
    AESCipher aesCipher = AESCipher(secretKey, nonce);
    String pwd64 = aesCipher.encrypt(password);
    debugPrint("加密后的密码 $pwd64");

解密同理。